Pregabalin, typically used to treat nerve pain or seizures, appears to offer extended pain relief for those with fibromyalgia, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Washington, DC.
Fibromyalgia is an often misunderstood syndrome that causes widespread chronic muscle pain and tenderness in 2 percent of the U.S. population, most commonly women. In addition to pain, fibromyalgia is often associated with fatigue, sleep disturbances and memory problems. Unfortunately, to date, no FDA-approved treatment has been available for this syndrome.
Researchers enrolled 1,051 participants in a six-week program of 300, 450 or 600 mg daily doses of pregabalin to optimize pain control and medication tolerance. On average, the population was 93% female, 88% white, had endured fibromyalgia for over seven years and measured their pain severity as 78 on a 100 point scale.
At the end of the 6-week program, 663 participants (63%) cited over 50% reduction in pain, and being "much" or "very much improved." Of these, 566 were randomized into a 26-week double-blind study to receive either pregabalin at the optimal dosage established during the 6 weeks prior or placebo. The primary goal of this six-month study, one of the longest control studies conducted to date, was to determine how long their therapeutic responses lasted.
One-fourth of placebo-treated patients saw worsening by day 7 as compared to day 34 for those on medication. By the end of the double-blind treatment, nearly twice (61%) as many placebo patients had lost response as compared to 32% of the patients on medication. The most common side effects of pregabalin were dizziness, somnolence, sinusitis, joint pain and anxiety. One death occurred each in the placebo and treatment arms of the trial, but neither was treatment-related.
"Fibromyalgia is a common and often debilitating pain syndrome," explains Leslie J. Crofford, MD, Gloria W. Singletary Professor of Rheumatology & Women's Health, University of Kentucky, Lexington, Kentucky, and an investigator in the study. "The results of this six-month study indicate pregabalin has a significant benefit in terms of longer-term pain relief for these patients."